1. Field of the Invention
The present invention relates to a socket wrench and more particularly, to an improved socket wrench including a plurality of socket members of varying sizes slidably assembled into the socket wrench in a telescopic manner so that upon utilizing the socket wrench, bolts or nuts having different sizes can be easily driven without any socket replacement.
2. Description of the Prior Art
Various types of conventional socket wrenches are well known in the art. Such socket wrenches have an adjustable members. However, such adjustable socket wrenches are expensive to manufacture, complicated in construction, and difficult in use. Such socket wrenches are shown in the U.S. Pat. Nos. 1,395,656, 1,432,263, 1,456,290, 1,502,044, 1,513,332, 2,743,641, 2,814,227, 3,253,486 and 3,541,901. Also, several types of conventional wrenches are utilized jaws so as to allow the user to adjust the jaws and then match the size of the socket to the size of bolts or nuts to be driven. However, such socket wrenches are not only cumbersome to carry out the adjustment operation but also complex in the overall structure. Therefore, it is difficult to fabricate such wrenches and thus it increases the manufacturing costs. Such socket wrenches are shown in the U.S. Pat. Nos. 2,582,444, 2,850,931, 2,884,826, 1,498,040, 2,580,247, 2,669,896, 2,701,489, 3,102,732, 3,724,299, 4,136,588 and 4,213,355.
The Korean Utility Model Publication No. 84-2675 discloses a socket wrench wherein several socket members are self-contained to enable the user to drive various sizes of bolts or nuts without any requirement for replacement of the socket members. However, the user first selects an appropriate socket member which corresponds to the size of a specific bolt or a nut. And then the user gets the selected socket member displace forward in an axial direction so that higher level of concentrative stresses are created in the course of driving operation since the socket member is utilized in an overhung condition. Also, in order to increase the strength of the socket member to a level enough to withstand those stresses, it is inevitable to increase wall thickness of the socket member and consequently rendering the socket member bulky and heavy. Therefore, this may be raised to a formidable problems in manufacturing and handling the socket wrench.
Further, the Korean Utility Model Publication No. 83-1343 discloses a socket wrench in which separate socket members are supplied independently so that the user may select a specific socket member of desired size and replace it for the previously assembled socket member, whenever it is necessary to drive bolts or nuts of different sizes. However, the socket wrench set forth above requires frequent replacement of the socket depending upon the size of bolts or nuts so that it is inconvenient for the user to handle it. In addition, separate socket members employed in the socket wrench have to be carried. Therefore, it is inconvenient to handle.